Advanced sensing technologies for active magnetic bearing systems: Trends and prospects

Active Magnetic Bearing (AMB) systems are integral to high-speed, precision-oriented, and energy-efficient industrial applications due to their contactless and friction-free operation. As their use expands into more dynamic and demanding environments, the need for advanced sensing technologies has become increasingly critical for ensuring rotor stability, fault detection, and thermal management. While prior reviews have focused narrowly on specific sensor types, this study offers a comprehensive overview of sensing technologies in AMB systems, covering position, vibration, thermal, and magnetic field sensors, each categorized into relevant subtypes. It highlights key advancements, including Micro-Electro-Mechanical Systems (MEMS), hybrid sensor integration, and AI-driven predictive maintenance. The review includes detailed analyses of recent AMB prototypes developed across research laboratories, outlining their sensor configurations and minimum sensing requirements. Performance metrics such as accuracy, response time, and sensitivity are examined and visualized through comparative illustrations. Mathematical models describing sensor behavior are provided to deepen technical understanding. Furthermore, the paper explores the application of artificial intelligence in AMB systems, detailing datasets, input features, training parameters, and evaluation metrics. Strategies for delay optimization through edge computing and real-time sensor data processing are also discussed. The paper addresses major challenges — such as electromagnetic interference, sensor calibration, and durability in extreme conditions — along with the interactions among them, for instance, how electromagnetic heating contributes to thermal drift. Finally, the paper proposes a forward-looking roadmap that aligns with Industry 4.0 standards, emphasizing sensor fusion, energy efficiency, and system scalability. This review aims to bridge current research gaps and foster innovation in next-generation AMB systems.